/*
 * File Name: AESUtil.java 
 * History:
 * Created by zhangzhiyong on 2013-9-26
 */
package com.denny.devdemo.clearer.worker;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.util.ArrayList;
import java.util.List;

import javax.crypto.Cipher;
import javax.crypto.CipherInputStream;
import javax.crypto.CipherOutputStream;
import javax.crypto.KeyGenerator;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;

import android.content.Context;
import android.os.Environment;

public class AESUtil {
    String key = "123456";
    /**
     * 初始化 AES Cipher
     * 
     * @param sKey
     * @param cipherMode
     * @return
     */
    private static Cipher initAESCipher(String sKey, int cipherMode) {
        // 创建Key gen
        KeyGenerator keyGenerator = null;
        Cipher cipher = null;
        try {
            keyGenerator = KeyGenerator.getInstance("AES");
            keyGenerator.init(128, new SecureRandom(sKey.getBytes()));
            SecretKey secretKey = keyGenerator.generateKey();
            byte[] codeFormat = secretKey.getEncoded();
            SecretKeySpec key = new SecretKeySpec(codeFormat, "AES");
            cipher = Cipher.getInstance("AES");
            // 初始化
            cipher.init(cipherMode, key);
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace(); // To change body of catch statement use File | Settings | File Templates.
        } catch (NoSuchPaddingException e) {
            e.printStackTrace(); // To change body of catch statement use File | Settings | File Templates.
        } catch (InvalidKeyException e) {
            e.printStackTrace(); // To change body of catch statement use File | Settings | File Templates.
        }
        return cipher;
    }

    /**
     * 对文件进行AES加密
     * 
     * @param sourceFile
     * @param fileType
     * @param sKey
     * @return
     */
    public static File encryptFile(File sourceFile, String fileType, String sKey) {
        // 新建临时加密文件
        File encrypfile = new File(Environment.getExternalStorageDirectory().getAbsoluteFile()+"/close.txt");
        InputStream inputStream = null;
        OutputStream outputStream = null;
        try {
            inputStream = new FileInputStream(sourceFile);
//            encrypfile = File.createTempFile("AES", fileType);
            outputStream = new FileOutputStream(encrypfile);
            Cipher cipher = initAESCipher(sKey, Cipher.ENCRYPT_MODE);
            // 以加密流写入文件
            CipherInputStream cipherInputStream = new CipherInputStream(inputStream, cipher);
            byte[] cache = new byte[1024];
            int nRead = 0;
            while ((nRead = cipherInputStream.read(cache)) != -1) {
                outputStream.write(cache, 0, nRead);
                outputStream.flush();
            }
            cipherInputStream.close();
        } catch (FileNotFoundException e) {
            e.printStackTrace(); // To change body of catch statement use File | Settings | File Templates.
        } catch (IOException e) {
            e.printStackTrace(); // To change body of catch statement use File | Settings | File Templates.
        } finally {
            try {
                inputStream.close();
            } catch (IOException e) {
                e.printStackTrace(); // To change body of catch statement use File | Settings | File Templates.
            }
            try {
                outputStream.close();
            } catch (IOException e) {
                e.printStackTrace(); // To change body of catch statement use File | Settings | File Templates.
            }
        }
        return encrypfile;
    }

    /**
     * AES方式解密文件
     * 
     * @param sourceFile
     * @return
     */
    public static File decryptFile(InputStream inputStream, String fileType, String sKey,Context context) {
        List<String> list = new ArrayList<String>();
        File decryptFile = new File(context.getFilesDir().getAbsoluteFile()+"/open.txt");
//        InputStream inputStream = null;
        OutputStream outputStream = null;
        try {
//            decryptFile = File.createTempFile("open", fileType);
            Cipher cipher = initAESCipher(sKey, Cipher.DECRYPT_MODE);
//            inputStream = new FileInputStream(sourceFile);
            outputStream = new FileOutputStream(decryptFile);
            CipherOutputStream cipherOutputStream = new CipherOutputStream(outputStream, cipher);
            byte[] buffer = new byte[1024];
            int r;
            while ((r = inputStream.read(buffer)) >= 0) {
                cipherOutputStream.write(buffer, 0, r);
            }
            cipherOutputStream.close();
//            BufferedReader reader = new BufferedReader(new FileReader(decryptFile));
//            String s = null;
//            while((s=reader.readLine())!= null){
//                list.add(s);
//                LogUtils.e("readline:"+s);
//            }
        } catch (IOException e) {
            e.printStackTrace(); // To change body of catch statement use File | Settings | File Templates.
        } finally {
            try {
                inputStream.close();
            } catch (IOException e) {
                e.printStackTrace(); // To change body of catch statement use File | Settings | File Templates.
            }
            try {
                outputStream.close();
            } catch (IOException e) {
                e.printStackTrace(); // To change body of catch statement use File | Settings | File Templates.
            }
        }
        return decryptFile;
    }
    
    public static void main(String [] args){
        try {
//            AESUtil.encryptFile(new File("d:\\path_mapping.txt"), "txt", "123456");
//            decryptFile(new File("d:\\AES.txt"), "txt", "123456");
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}
